Myanmar has been in turmoil since a military coup in February sparked nationwide protests and a deadly crackdown on dissent.

Detained since the putsch, Suu Kyi, 76, faces a raft of charges including illegally importing walkie talkies, sedition and corruption, and faces decades in jail if convicted.

The latest charges entail "election fraud and lawless actions", state-run newspaper Global New Light of Myanmar reported, without giving details on when court proceedings would begin.

Fifteen other officials -- including former president Win Myint and the former chairman of the election commission -- face the same charge, the report added.

Suu Kyi's National League for Democracy party (NLD) saw its support increase in the 2020 vote compared to the 2015 election, trouncing a military-aligned party.

But the junta has cited fraud during the poll as its reason for seizing power and ending Myanmar's democratic interlude.

In July, it cancelled the results of the polls, announcing it had uncovered more than 11 million instances of voter irregularities.

Junta chief Min Aung Hlaing said fresh elections would be held and a state of emergency lifted by August 2023, extending the military's initial timeline given when it seized power.

In a report on the 2020 polls, the Asian Network for Free Elections monitoring group had said it was "by and large, representative of the will of the people".

- 'Deep concern' -

"The junta is using spurious claims of electoral fraud as a key justification for its coup," International Crisis Group's Myanmar senior advisor Richard Horsey told AFP.

"Having failed after much effort to identify more than a handful of people who voted twice, it is now going after NLD leaders," he said.

"But Aung San Suu Kyi and the NLD had overwhelming support from voters, so guilty verdicts will convince no one."

The junta has threatened to dissolve the NLD and last month jailed Win Htein, a close Suu Kyi aide and high-ranking leader, to 20 years on treason charges.

Suu Kyi is already on trial for flouting coronavirus restrictions while campaigning ahead of the election.

Journalists have been barred from attending proceedings at the special court in the military-built capital Naypyidaw, and the junta recently muzzled her legal team from speaking to the media.

Suu Kyi appeared for the latest hearing in her trial for allegedly importing and possessing illegal walkie talkies on Monday, a source with knowledge of the matter told AFP.

A verdict for her trial on breaching Covid-19 regulations is expected in December. She faces three years in jail if found guilty.

Last week, the UN Security Council expressed its "deep concern" about the unrest in Myanmar and called for an "immediate cessation of violence" and for efforts to ensure that civilians are not harmed.

More than 10,000 people have been arrested since the coup, according to a local monitoring group.